The strong correlation of charge, lattice, spin and orbital degrees of freedom in manganites provides a rich phase diagram for La1-xSrxMnO3 (LSMO) that ranges from canted antiferromagnetism (AFM) to ferromagnetism (FM) to paramagnetism (PM). Here we report the growth of self-assembled (La0.67Sr0.33MnO3/La0.73Sr0.27MnO3/SrTiO3) thin-film heterostructures that show unusual magnetic properties like exchange bias, spontaneous magnetic reversal and inverted hysteresis, with substantial suppression of octahedral tilts in La-poor region. Using first-principles calculations, we provide a theoretical understanding of the correlation of structural and magnetic properties observed in these self-assembled heterostructures and complement the experiments. We address the following three questions: (I) How does change of x in La1-xSrxMnO3 affect magnetism? (II) What is the origin of the observed exchange bias? and (III) How do we explain the suppression of octahedral tilts in La0.67Sr0.33MnO3 identified as critical for the novel magnetic properties?.

*This work is supported by DOE grant numbers DE-FG02-09ER46554 and DE-SC0002136.